The present invention relates to a thermal transfer printer, and, more particularly, to a line type thermal transfer printer having an ink film ribbon interchanging mechanism which provides a plurality of interchangeable ink film ribbons and is capable of carrying out, for example, a color printing operation.
In a conventional line type thermal transfer printer such as disclosed in, for example, the Japanese Patent laid-open publication No. 204575/1984, a thermal head is pressed against a platen through a recording paper and an ink film ribbon.
The thermal head is withdrawn to the withdrawal position, while the recording paper and the ink film ribbon are moved relative to each other, to thereby release the thermal head from the pressure for urging the thermal head against the platen. The withdrawal distance of the thermal head during this time is slightly greater than a total thickness of the recording paper and the ink film ribbon in the laminated state.
This type of line type thermal transfer printers are generally provided with only one roll of the ink film ribbon and, in such thermal transfer printers, the necessity of the interchanging a plurality of the ink film ribbons during the printing operation is not taken into consideration.
An object of the present invention resides in providing a thermal transfer printer wherein a plurality of ink film ribbons can be used selectively in accordance with a desired color in which an object image is to be printed.
Another object of the present invention resides in providing a thermal transfer printer wherein an useless feeding of an ink film ribbon can be prevented regardless of the letter pattern in use.
Yet another object of the present invention resides in providing a thermal transfer printer wherein the operating cost of the thermal transfer printer can be reduced.
A further object of the present invention resides in providing a thermal transfer printer wherein a plurality of ink film ribbons can be interchangeable.
Another object of the present invention resides in providing a thermal transfer printer wherein the types of ink film ribbons can be identified.
A still further object of the present invention resides in providing a thermal transfer printer wherein a color printing operation can be carried out.
A further object of the present invention resides in providing a thermal transfer printer wherein an image can be printed in gradually-varying colors when ink film ribbons of different density are provided within ink ribbon cassettes.
Yet another object of the present invention resides in providing a thermal transfer printer wherein a monochromatic printing ink film ribbon and a color printing ink film ribbon can be installed.
Yet another object of the present invention resides in providing a thermal transfer printer wherein a draft copy function can be furnished when an ink film ribbon of an inferior printing quality is set in the thermal transfer printer with a regular ink film ribbon of a high printing quality.
A still further object of the present invention resides in providing a thermal transfer printer wherein a beautiful and truly black printing can be obtained without a mixture of inks of three primary colors.
In accordance with the present invention a thermal transfer printer is provided which includes a case, side plates provided at both sides of the case, a platen provided between the side plates, rollers provided between the side plates and being in press-contact with the platen and an ink film ribbon wounded around a send-out roll being taken up around a take-up roll through the platen. A recording paper is disposed opposite to an ink layer on the ink film ribbon being sent to a printing position by the platen. A thermal head is provided having heating elements disposed in a main scanning direction, with the heating elements of the thermal head being pressed against the platen through the ink film ribbon and the recording paper. A feeding means for the recording paper is provided in the case communicating to the platen through a connecting means, with a feeding means for the ink film ribbon being provided in the case. A supporting means for the thermal head is provided in the case and is movable between the side plates. A driving means for the thermal head supporting means provided in the case so as to transmit a force, with the thermal head being adapted to be brought against the ink film ribbon being heated in accordance with a recording information and an ink image is transferred to and recorded on a surface of the recording paper. A driving means is provided which is capable of setting a clearance between the platen and the thermal head to a width which is not less than a maximum diameter of one roll of the ink film ribbon and means are provided for guiding the ink film ribbon to a predetermined recording position so as to position the ink film ribbon.
The ink ribbon cassette, which contains a first ink film ribbon is moved as required in accordance with a recording information to the printing position in which the thermal head is disposed. The first ink ribbon cassette is changed after a printing with the first ink film ribbon has been completed to a second ink ribbon cassette which contains a second ink film ribbon.
The guiding means for a plurality of the ink ribbon cassettes in the predetermined positions therein is adapted to be rotated for sending out the first ink ribbon cassette to be used and receiving the second ink ribbon cassette by an ink ribbon cassette-driving motor.
The guiding means for a plurality of the ink ribbon cassettes in the predetermined positions therein is adapted to be moved forward and backward for sending out the first ink ribbon cassette to be used and receiving the second ink ribbon cassette by an ink ribbon cassette transfer means which can be moved to a position by driving an ink ribbon cassette-moving motor.
The guiding means for a plurality of the ink ribbon cassettes in the predetermined positions therein is adapted to be changed by withdrawing from the first ink film ribbon in the first ink ribbon cassette to the second ink film ribbon in the second ink ribbon cassette by an ink ribbon cassette fixing member which can be moved by an ink ribbon cassette lifting and lowering motor.
According to the present invention, a plurality of ink film ribbons or ink ribbon cassettes can be used selectively in accordance with a desired color in which an object image is to be printed, so that the useless feeding of an ink film ribbon can be prevented regardless of the letter pattern in use.
Since the ink film ribbon is not uselessly fed, the operating cost can be reduced to a low level. A black image can be printed in black ink which is not a mixture of ink of three primary colors. Therefore, a color thermal transfer printer, which enables beautiful, truly black printing to be done, can be obtained.